Plant Conservation Challenges in the Bahama Archipelago

The Bahamian archipelago has a rich flora with 89 endemic species. An international symposium held at Nassau in October 2012 to celebrate the 30th anniversary of the publication of the “Flora of the Bahama Archipelago” provided a forum to discuss plant conservation issues on these islands. This article builds on conclusions from this symposium and results from joint plant conservation research projects among the authors. The two main conservation challenges for these islands are: (1) environmental uncertainties derived from global warming and associated sea level changes and (2) the need for increased plant conservation awareness among the predominant urban population of the archipelago. Legal tools and biodiversity international agreements in place for The Commonwealth of the Bahamas can facilitate mechanisms for effective plant conservation. Further legal developments need to be established in The United Kingdom Overseas Territory of The Turks and Caicos Islands. There is an urgent need to redevelop the Botanic Garden of Nassau and designate it as the national botanic garden of The Bahamas. Further research related to the taxonomy, biology, conservation status, and distribution of the endemic species is urgently needed. Research initiatives pertinent to the detrimental effect and biology of invasive species are also lacking. The heterogeneous environments and uneven distribution of human populations across the archipelago are major challenges for conservation. Finally because of the political and economic status of The Bahamas and The Turks and Caicos, conservation agencies from the archipelago do not have easy access to international or British/European Union funds for global conservation initiatives.     

The New York Botanical Garden and the making of The Bahama Flora, 1920

In the late 1800s and early 1900s, The New York Botanical Garden, under the leadership of its Director-in-Chief, Nathaniel Lord Britton, launched an intensive program of exploration and publication on the plants of the Western Hemisphere, particularly in the northern Caribbean region. One major geographic focus during this period was the Bahama archipelago, resulting in the 1920 publication The Bahama Flora. Dr. Britton personally led four expeditions to the Bahamas between 1904 and 1907, but most of his effort on this project was devoted to coordinating and seeking funding for some two dozen expeditions from 1904 to 1911 undertaken by collaborators, most notably Charles Frederick Millspaugh of the Field Museum, co-author with N.L. Britton of The Bahama Flora. In total, the Flora reported 1,982 species. The present paper recounts the itineraries of the expeditions and provides examples of the principal botanical discoveries realized in the making of The Bahama Flora.     

A new species of Eupatorium (Compositae) endemic to Grand Bahama Island

A new species,Eupatorium correlliorum, is described from Grand Bahama Island, Bahamas, where it is apparently endemic.     

Brazilian pepper—Its impact on people,animals and the environment

Native to Brazil,Schinus terebinthifolius Raddi, of the family Anacardiaceae, has been commonly cultivated in Florida for over 50 years as a dooryard ornamental. Use of its sprays of showy red fruits for Christmas decoration gave rise to the popular misnomer “Florida holly.” Too late it was found to become a large, spreading tree; aggressive seedlings began springing up near and far. Jungles ofSchinus have crowded out native vegetation over vast areas of Florida and the Bahamas, as in all the islands of Hawaii. When in bloom, the tree is a major source of respiratory difficulty and dermatitis; the fruits, in quantity, intoxicate birds and cause fatal trauma in four-footed animals. The abundant nectar yields a spicy commercial honey and beekeepers are opposed to eradication programs.     

A preliminary survey of yeasts isolated from marine habitats at Abaco Island,The Bahamas

Littoral zone marine sediment and sand, spiny lobster and conch were examined for yeasts. Nineteen yeast species were found to exist in varying abundance. Previous studies in the series examined the marine fungi (17), fresh water fungi (16), and keratinophilic fungi (15) of Abaco Island, The Bahamas.     

Taxonomy and distribution of Chaptalia dentata and C. Albicans (Asteraceae: Mutisieae)

Chaptalia dentata (L.) Cass. andC. albicans (Sw.) Vent. ex Steudel incorrectly have been recognized as conspecific in recent treatments. Although they are vegetatively similar, they differ in features of the flowers and fruits—especially the mature achenes. Both species occur in the Bahamas and the Greater Antilles of the West Indies:Chaptalia dentata is endemic to that area, absent only from Jamaica;C. albicans is more widespread, as it occurs in Jamaica as well as in scattered localities on the American mainland—southern Florida, various localities in Belize, Honduras, and Guatemala, and the Mexican states of Veracruz, San Luis Potosí, Chiapas, and Yucatán.     

The Bahamian Flora: Plant Exploration,Living Collections,and DNA – A Journey Started in 1963

Dr. John Popenoe was Director of Fairchild Tropical Botanic Garden (FTBG) between 1963 and 1989. Dr. Popenoe was a strong supporter of the Bahamian flora, and in 1963 he obtained extramural funds to develop a living collection focusing on Bahamian plants that was established in FTBG. During his tenure FTBG supported the publication of the latest comprehensive flora of this archipelago. A project initiated by the first FTBG herbarium curator, William Gillis, but published by Donovan and Helen Correll (with illustrations of Priscilla Fawcett) in 1982. This living collection of Bahamian plants has supplied plant material for molecular phylogenetic studies worldwide. There are DNA phylogenies for only 10 of the 89 Bahamian endemics; most of the material of these phylogenies came from plants from these collections (three species) and/or from fragments of herbarium specimens collected by Donovan Correll (six species). Only two of the species included in these phylogenies are from collections unrelated to FTBG. Excluding species restricted to the Bahamas, material from 14 Caribbean Island endemics that are part of these collections has been used in phylogenetic studies. The available molecular phylogenies show that the Bahamian endemics are closely related to species from the West Indies or continental areas of the Caribbean Basin. There is also a paucity of population genetic studies based on DNA markers focusing on Bahamian plants. Only two of the four available population genetic studies are for a Bahamian endemic taxon.     

Neotropical nymphoides (Menyanthaceae): Meso-American and west indian species

Studies ofNymphoides (Menyanthaceae) in Mexico, Central America, and the West Indies indicate that three species are present in this region, all of which are members of theNymphoides indica complex. White-flowered plants of Meso-America, the Antilles, and South America traditionally have been referred toN. humboldtiana but are identical to the otherwise Old WorldN. indica and must be called by the latter name. The Mexican and GuatemalanNymphoides fallax, described in this paper, differs fromN. indica in having winged yellow petals with a stipitate basal tuft of hairs, consistently yellow anthers, larger seeds, and higher altitudinal occurrence. Yellow-flowered plants of the Bahamas and Cuba are considered to represent a third species,N. grayana, which resembles plants of southern Brazil and southern Africa in flower color and morphology. However, because of the geographic distribution and unique ultraviolet-light emittance characters ofN. grayana and the still uncertain relationships of the Brazilian and African populations, this third taxon is provisionally retained at the specific level pending further study of those populations.     

NDRG1 expression is related to the progression and prognosis of gastric cancer patients through modulating proliferation,invasion and cell cycle of gastric cancer cells

N-myc downstream-regulated gene 1 (NDRG1) has been proposed as a tumor suppressor gene in many different types of tumors, but its potential function and corresponding mechanism are not yet fully elucidated. This study aims to detect the possible function of NDRG1 in gastric cancer progression. In this study, 112 paired gastric cancer tissues and corresponding nonmalignant gastric tissues were utilized to identify the differential protein expression of NDRG1 by immunohistochemistry and its clinical significance was analyzed. Furthermore, 49 of 112 paired gastric specimens were used to detect the differential mRNA expression by real-time PCR. The over expression of NDRG1 in human gastric cancer cell line AGS by PcDNA3.1–NDRG1 transfection was utilized to detect the role of NDRG1 in regulating the biological behavior of gastric cancer. NDRG1 expression was significantly decreased in primary gastric cancer tissues, compared with its corresponding nonmalignant gastric tissues (p < 0.05), and its decreased expression was significantly associated with lymph node metastasis (p < 0.01), invasion depth (p < 0.01) and differentiation (p < 0.05). Additionally, the overall survival rate of gastric cancer patients with high expression of NDRG1 was higher than those with low expression during the follow-up period. NDRG1 overexpression suppressed cells proliferation, invasion and induced a G1 cell cycle arrest in gastric cancer. Furthermore, the down-regulation of NDRG1 in gastric cancer metastatic progression was correlated to E-cadherin and MMP-9. Our results verify that NDRG1 acts as a tumor suppressor gene and may play an important role in the metastasis progression and prognosis of gastric cancer.     

Centric diatoms from Lake Frolikha (Transbaikal area) and peculiarities of distribution of some taxa in Asia

The species composition of centric diatoms from Lake Frolikha (Transbaikal area) has been studied. The lake is located on the eastern shore of Lake Baikal and connected with it by a river. Twenty-three species of Centrophyceae from 7 genera (Aulacoseira, Cyclostephanos, Cyclotella, Discostella, Handmania, Pliocaenicus, and Stephanodiscus) have been found. The most represented genus is Aulacoseira (11 species). Fifteen species and 4 genera are new for the lake record. All revealed species are known in other lakes of the Baikal region; however Baikal endemics are absent in Lake Frolikha. The flora of centric diatoms in Lake Frolikha can be divided into two groups. The first group includes taxa common in Lake Baikal, and the second group includes taxa not typical for Lake Baikal. The level of differences between flora in Lake Baikal and Lake Frolikha is high (43%) despite the close location and connection to the river. An analysis of distribution of interesting species in Asia is presented.     

Identification of nucleolus-localized PTEN and its function in regulating ribosome biogenesis

The tumor suppressor PTEN is a lipid phosphatase that is found mutated in different types of human cancers. PTEN suppresses cell proliferation by inhibiting the PI3K-Akt signaling pathway at the cell membrane. However, PTEN is also demonstrated to localize in the cell nucleus where it exhibits tumor suppressive activity via a different, unknown mechanism. In this study we report that PTEN also localizes to the nucleolus and that nucleolar PTEN plays an important role in regulating nucleolar homeostasis and maintaining nucleolar morphology. Overexpression of nuclear PTEN in PTEN null cells inhibits Akt phosphorylation and reduces cell size. Knockdown of PTEN in PTEN positive cells leads to nucleolar morphologic changes and an increase in the proportion of cells with a greater number of nucleoli. In addition, knockdown of PTEN in PTEN positive cells increased ribosome biogenesis. These findings expand current understanding of function and relevance of nuclear localized PTEN and provide a foundation for the development of novel therapies targeting PTEN.     

Relationship of Cob characters with Grain Morphology in Maize (Zea mays,Poaceae)

Twenty varieties of maize (Zea mays, Poaceae) were studied through 11 attributes in three to seven randomly selected plants of each variety with a view to understanding the effect of cob characters on technologically desirable grain qualities. Canonical discriminant analysis showed thatproductivity (determined by total grain weight/cob, cob diameter and average grain weight) was the most discriminating among varieties followed by round grains fraction (represented by whole top and middle flat grains, number of rows and grain count/surface area), middle flat grains (composed of middle flat grains and grain count/surface area) and shape of the cob (determined by shape index, total grain weight/cob and cob diameter), which accounted for 35.1, 18.3, 12.2, and 9.8% of the total variance, respectively. In the light of these results, tentative norms have been suggested to evolve maize varieties of superior technological properties and yet retain high productivity. A cylindrical cob of large diameter with highest number of grains/area and smallest possible number of rows together constituted an ideal combination to achieve the objectives. Such possibilities in the light of available information are discussed.     

Molecular cloning,structural analysis,and expression of zona pellucida glycoprotein ZP3 gene from Chinese zokor,Myospalax fontanierii

The zona pellucida 3 (ZP3) plays a crucial role in reproductive immunology. We obtained a full-length cDNA encoding Chinese zokor ZP3, using rapid amplification of cDNA ends-polymerase chain reaction (RACE-PCR). The cDNA contains an open reading frame of 1269 nucleotides encoding a polypeptide of 422 amino acid residues. The amino acid sequence has a high degree of homology with those of hamster (78%), mouse (76%), and rat (74%). XhoI and SacI sites after restriction give an1158 bp fragment of zokor ZP3 cDNA, excluding the signal sequence and transmembrane-like domain, which was cloned under the phage T7 promoter-lac operator control in the pET-28a(+) vector. Recombinant pET-zokorZP3(r-ZP3) was expressed as a poly-histidine fusion protein in E. coli strain BL21 (DE3). Optimum expression of r-ZP3 was observed at 28°C, 1 mM IPTG and 2 h of inducing. The purified protein was tested by Western blot.     

Molecular characterization of argininosuccinate synthase and argininosuccinate lyase from the liver of the African lungfish Protopterus annectens,and their mRNA expression levels in the liver,kidney, brain and skeletal muscle during aestivation

Argininosuccinate synthase (Ass) and argininosuccinate lyase (Asl) are involved in arginine synthesis for various purposes. The complete cDNA coding sequences of ass and asl from the liver of Protopterus annectens consisted of 1,296 and 1,398 bp, respectively. Phylogenetic analyses revealed that the deduced Ass and Asl of P. annectens had close relationship with that of the cartilaginous fish Callorhinchus milii. Besides being strongly expressed in the liver, ass and asl expression were detectable in many tissues/organs. In the liver, mRNA expression levels of ass and asl increased significantly during the induction phase of aestivation, probably to increase arginine production to support increased urea synthesis. The increases in ass and asl mRNA expression levels during the prolonged maintenance phase and early arousal phase of aestivation could reflect increased demand on arginine for nitric oxide (NO) production in the liver. In the kidney, there was a significant decrease in ass mRNA expression level after 6 months of aestivation, indicating possible decreases in the synthesis and supply of arginine to other tissues/organs. In the brain, changes in ass and asl mRNA expression levels during the three phases of aestivation could be related to the supply of arginine for NO synthesis in response to conditions that resemble ischaemia and ischaemia–reperfusion during the maintenance and arousal phase of aestivation, respectively. The decrease in ass mRNA expression level, accompanied with decreases in the concentrations of arginine and NO, in the skeletal muscle of aestivating P. annectens might ameliorate the potential of disuse muscle atrophy.     

Systematics,Taxonomy, and the New Flora of the Bahamian Archipelago

A history of botanical exploration in the Bahama Archipelago is given, and is presented in three sections. The first section begins with the earliest botanical collections in 1700 by Thomas Walker and describes, in chronological order, botanical collections made up to 1920, when Britton and Millspaugh published the first Bahama flora. The second section chronicles botanical research in the archipelago after 1920, up until the publication by Correll and Correll of the Flora of the Bahama Archipelago in 1982. The third section describes plant research in the archipelago between 1982 and the present day. Following a brief rationale for the need for a new flora, the present research toward the flora is discussed, and an example of changes in the flora since 1982 is presented, with changes in the fern flora tabulated.     

The influence of repetitive thermal stresses on the dominance of reef-building Acropora spp. (Scleractinia) on coral reefs of the Maldive Islands

The distribution and size-age structure of Acropora corals were studied in two Maldivian atolls that differ in their geographic position and sea surface temperature regimes. The frequency and strength of thermal anomalies for the last 2 decades had a significant influence on the abundance, mortality rates, and age structures of acroporid communities. The long-term temperature amplitude was higher and the maxima were more pronounced in the northernmost Ihavandippolu Atoll than those in the equatorial South Huvadhoo Atoll. These differences resulted in a 10.4% mean cover of Acropora at Ihavandippolu Atoll, whereas the Acropora cover in the South Huvadhoo Atoll reached 59.5%. In the northern atoll, the coral mortality rate after the 2010 thermal anomaly was 3 times higher than that in the southern atoll. Younger acroporid colonies (up to 2 years old) dominated the northern atoll reefs, while the southern atoll showed a high proportion of older mature colonies. In both atolls, healthy table colonies of Acropora cytherea with a disk diameter greater than 2 m were observed that apparently survived three thermal anomalies since 1998. The mechanisms of acclimatization of Acropora and the prospects for its dominance in the Maldives under changing environmental conditions are discussed.